Resistance R1 = 4 Ω, R2 = 6 Ω, connect the parallel connection to the power supply, the total power consumed by the power supply is 40W, and the output power of the power supply is 38.4w? Resistance R1 = 4 ohm, R2 = 6 ohm, connected in parallel to the power supply, the total power consumed by the power supply is 40 W, the output power of the power supply is 38.4 W, calculate the electromotive force E and internal resistance R of the power supply

Resistance R1 = 4 Ω, R2 = 6 Ω, connect the parallel connection to the power supply, the total power consumed by the power supply is 40W, and the output power of the power supply is 38.4w? Resistance R1 = 4 ohm, R2 = 6 ohm, connected in parallel to the power supply, the total power consumed by the power supply is 40 W, the output power of the power supply is 38.4 W, calculate the electromotive force E and internal resistance R of the power supply

Rtotal = R4 / / R6 = 2.4 Ω
The total current in the circuit is I = 38.2 / 2.4 open root
P power = 40-38.4 = I ^ 2 * r = 0.1 ohm
E = I * (r total + R) = 4 * (2.4 + 0.1) = 10V

A motor coil resistance is 1 ohm, connected to 220 V power supply, motor power consumption is 4.4 W
Ask: 1: what is the current intensity when the motor is working? 2: how much electric energy is consumed by the motor per hour? How much electric energy is lost by the motor coil in 3:1s clock?

(1):I=P/U=4.4/220=0.02A
(2):W=4.4*3600=
(3) : w = 0.02 * 0.02 * 1 * 1 = please do it yourself

A 100 ohm resistor with a rated power of 4W is connected to a 20V power supply____ If connected to 40V power supply_____ .
A. The power of the resistor is less than its rated power and can be used normally
B. The power of the resistor is equal to its rated power and can be used normally
C. The power of the resistor is greater than its rated power and cannot be used normally
I hope you can do me a favor and help me analyze it

B. C, according to u ^ 2 / r = P, once the power supply is greater than 20, the current is too large, so it cannot be used normally

The rated power of a 1000 ohm resistor is 1W. What is the rated current and voltage of the resistor

P=U²/R,U=√PR=31.6V.P=UI,I=P/U=0.0316A

① The relationship between voltage of consumer and power supply in series
② It is said that the sum of the voltages of the consumers on each branch is equal to the supply voltage. Does that mean the sum of the consumers on each branch? If not, please ignore this extra question and answer the two questions outside the brackets
Try to explain each question clearly in one sentence

1.U=U1+U2+------
2.U=U1=U2=------

Does the voltage of a simple circuit depend on the consumer or the power supply?

The direction of the upstairs answer is wrong. In the circuit, the voltage of the power supply is certain in theory. The reason for the change is only because of the circuit loss or use, resulting in voltage drop. As long as the power of the power transformer is enough, and your electrical appliances are within the theoretical range, the voltage drop can be ignored, unless you use a longer power supply in the circuit

Why is the voltage of power supply equal to that of electric appliance?
Use a voltmeter to measure the voltage. When the voltmeter is connected in parallel with all electrical appliances, why do you say that the voltage value obtained is the voltage value of all electrical appliances and the voltage value of the power supply? The voltage value of electrical appliances is equal to the voltage value of the power supply? Why?
Use electrical appliances in series

Series connection of electrical appliances is equivalent to series connection of resistors. The sum of voltage drop of all electrical appliances is equal to the power supply voltage, which is the law of loop voltage. The voltmeter is connected to the power supply in parallel, and the measured voltage is the power supply voltage, which also meets the law of loop voltage

Voltage is the reason for what in the circuit, the role of the power supply is to gather a lot of what in the positive pole of the power supply, and gather a lot of what in the negative pole of the power supply
Eighth grade physics second semester people's education experimental edition

The voltage is the cause of current generation in the circuit, and the function of the power supply is to gather a large number of positive charges at the positive pole of the power supply and a large number of negative charges at the negative pole of the power supply

What is the reason for the formation of the circuit voltage, the role of the power supply is to provide at both ends of the circuit?

The voltage is the reason that forces the free charge to move in a directional direction to form a current,
The function of the power supply is to provide the potential difference between the two ends of the circuit, that is, to provide voltage

Why should there be power supply in the circuit? What is the function of voltage?
These functions I know which master can help me describe accurately with language

Only when there is a power supply can there be a potential difference, and only when there is a potential difference can there be the flow of electrons, so that the current can be generated. The power supply is to provide the potential difference, just like when there is a water pressure difference when the terrain is high, the water will flow down
The voltage is the potential difference, which makes the electrons flow in a directional direction and produce an electric current